New Delhi, Aug. 17: A week after Prime Minister Manmohan Singh challenged the Left to accept the nuclear deal or withdraw support, the CPM and the CPI today decided to lob the ball back in his court with a message — “save the deal or save your government, you can’t do both”.

The CPM politburo and the CPI central secretariat’s official response will be made public tomorrow, but both parties gave ample indication that the countdown had begun and it was only a matter of time and detail before a formal “divorce” came about.

By placing the onus of the UPA regime’s survival on the Congress, the Left may also drive a wedge between the Prime Minister and his party.

Congress leaders, who want to avoid mid-term polls at any cost, are ready for a “compromise” that could include putting the nuclear agreement “in cold storage” for now, sources said.

But such a move would mean not just an enormous loss of face for Singh but also “seriously damage India’s image in the world”, sections in the government feel, hinting that any compromise on the Left’s terms could lead to a divorce between the party and the Prime Minister.

Taking a much harder line in public than big brother CPM, CPI general secretary A.B. Bardhan said the situation had become “untenable” and the Left parties would soon take a joint decision on support to the government.

In an interview to the Times Now channel, he had underlined the “irreconcilable” differences with the government on growing strategic ties with the US. The honeymoon was over and they could “file divorce papers” soon, he added.

Sticking to the hackneyed marital metaphor, CPM leader Prakash Karat told reporters that the “honeymoon may be over but the marriage can go on”. But before the government could heave a sigh of relief, Karat clarified that he had only said it as “a joke”.

CPM leaders privately echoed Bardhan. “It is for the Congress to decide whether to proceed with the agreement or retain the government,” a leader said, stressing the Left would not allow any more steps on the deal.

Their demand that the government not “operationalise” the deal meant that if it went ahead with negotiations with the International Atomic Energy Agency or the Nuclear Suppliers Group ahead of a formal signing, the Left would withdraw support.

The government’s efforts to reach out to “moderates” in the CPM — Pranab Mukherjee has met Sitaram Yechury a couple of times and Singh had Buddhadeb Bhattacharjee over for dinner tonight — has made no difference to the leadership’s decision to take a strong line on the deal, the sources said. After spending an hour and 40 minutes with Singh, Bhattacharjee said the meeting was “good, very good”.

In fact, the government’s “Track II” efforts have not gone down well with rank-and-file members who feel that the Congress is treating the CPM as a “bourgeois” party and trying to exploit perceived “differences” within the party leadership.As one member put it: “Every party member has grown up hating US imperialism. On this issue, the entire party – in Bengal, Kerala, and elsewhere – will back the line fully.”

With party conferences from the branch level upwards scheduled to start from September ahead of the CPM’s 19th congress and the CPI’s 20th congress early next year, the Left’s stand against “imperialism” will go down to the grassroots and shore up the hardliners’ position, the sources said.

The Left parties have yet to work out the “modalities” of the divorce in case the government flatly refuses to spike the nuclear deal and several options are under consideration, the sources said. But the bottomline will be that a Left-backed government “cannot allow India to go ahead with an agreement that binds us to the US in perpetuity”.